The documents have been classified for more than 50 years, and represent the final 1% of government files relating to the assassination. A law enacted in 1992 mandated they be made public within 25 years, by October 26, 2017.

Historians and conspiracy theorists alike are hoping the files will shed light on the infamous day in Dallas that has generated decades of intrigue and countless questions.

Here are some of the unanswered questions the files could resolve:

What did the government know about Lee Harvey Oswald?

The full extent of what the FBI and CIA knew about Lee Harvey Oswald, the ex-Marine and known Marxist who shot Kennedy on November 22, 1963, is still unclear.

We know that Oswald traveled to the Soviet Union in 1959, the same year he was discharged from the Marines, in an effort to renounce his US citizenship and gain Soviet citizenship. When he failed to become a Soviet citizen, he returned to the US in 1962 with his wife and newborn daughter.

The FBI and CIA were both monitoring Oswald, including when he made a six-day trip to Mexico City a few weeks before the assassination.

Thursday's batch of Kennedy files could contain information on CIA officials from the 1960s who knew about Oswald's activities, and could fill in the gaps of what the two agencies knew about him.

What was Oswald doing in Mexico City before the assassination?

Lee Harvey Oswald.Wikimedia CommonsA key element that historians hope is addressed in Thursday's document release is Oswald's six-day trip to Mexico City about eight weeks before the assassination.

A House committee concluded that Oswald had meetings at the consulates of both Cuba and the Soviet Union during his trip. Officials believe Oswald was attempting again to obtain Soviet citizenship along with a visa to visit Cuba. His attempts were unsuccessful.

However, documents released in 1999 show that after Oswald returned to the US, someone impersonating him made calls to the Soviet embassy and the Cuban consulate, adding a layer of mystery to this crucial period of the timeline.

John Tunheim, a federal judge who was chairman of Assassination Records Review Board, said documents relating to Oswald's Mexico trip weren't released because they could be damaging to the US's standing with Mexico.

"We received a full court press — not only from the State Department, but the CIA and other agencies, as well — not to release, because it was thought to be detrimental to our relationship with the Mexican government at the time," Tunheim told NBC News.

But now, "it doesn't matter anymore," he said. "The political party in charge then is no longer the controlling party in Mexico today."

Was there another shooter?

One of the most widely popular conspiracy theories concerning the Kennedy assassination was that Oswald was not the only shooter. However, nearly all investigations concluded that Oswald acted alone, and the theory has been largely discredited by photographic and video analysis of the incident.

Thursday's files could finally put it to bed with classified accounts of what happened in the moments after the gunman opened fire.